RICE SCIENCE ›› 2012, Vol. 19 ›› Issue (2): 117-124.

• Research Paper • Previous Articles     Next Articles

Evaluation of Agronomic Traits in Chromosome Segment Substitution Lines of KDML105 Containing Drought Tolerance QTL under Drought Stress

  1. 1Center for Agricultural Biotechnology, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand; 2School of Agriculture and Natural Resources, University of Phayao, Phayao 56000, Thailand; 3Rice Gene Discovery Unit, National Center of Genetic Engineering and Biotechnology, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand; 4Sakon Nakhon Rice Research Center, Sakon Nakhon 47000, Thailand; 5Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand; 6Rice Science Center, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand
  • Online:2012-06-28 Published:2012-04-18
  • Contact: Theerayut TOOJINDA
  • Supported by:

    National Center for Genetic Engineering and Biotechnology (BIOTEC), Thailand and was partially funded by the Center of Excellence on Agricultural Biotechnology, Science and Technology Postgraduate Education and Research Development Office, Office of Higher Education, Commission, Ministry of Education (AG-BIO/PERDO-CHE), Thailand.

Abstract: Drought is a major abiotic constraint to rice production in rainfed lowland and insufficiently irrigated areas. The improvement of drought tolerant varieties is one of the strategies to reduce the negative effects of drought. Quantitative trait loci (QTLs) for primary and secondary traits related to drought tolerance (DT) on chromosomes 1, 3, 4, 8 and 9 that determined from double haploid lines derived from a cross between CT9993 and IR62266 were introgressed and dissected into small pieces in the genetic background of Khao Dawk Mali 105 (KDML105) to develop chromosome segment substitution line (CSSL) population. The CSSLs were evaluated at the reproductive stage for their agronomic performance and yield components under drought stress, and results were compared with irrigated condition. The flowering of CSSL lines was 6 to 7 d earlier than KDML105. The mean values of grain yields in the CSSLs were higher than KDML105 under drought and irrigated conditions. At irrigated condition, the grain yields of introgression lines carrying DT-QTLs from chromosomes 4 and 8 were higher than that of KDML105, whereas other traits showed little difference with KDML105. Analysis indicated that grain yield has positive correlation with plant height, tiller and panicle number per plant, and total grain weight per plant under drought stress while negatively correlated with days to flowering. As mentioned above, CSSLs showing good adaptation under drought stress can be used as genetic materials to improve drought tolerance in Thai rainfed lowland rice breeding program, and as materials to dissect genes underlying drought tolerance.

Key words: chromosome segment substitution lines, drought tolerance, quantitative trait loci, drought stress, Jasmine rice